Former first lady Barbara Bush was discharged from Houston Methodist Hospital on Saturday , a family spokesman said .

`` I can not thank the doctors and nurses at Houston Methodist enough for making sure I got the best treatment and got back to George and our dogs as quickly as possible , '' Bush said .

She was released after six days of treatment for pneumonia , a family statement said .

Bush , 88 , is the wife of the 41st U.S. president , George H.W. Bush , and the mother of the 43rd , George W. Bush . President Barack Obama and former President Bill Clinton sent their best wishes to Mrs. Bush for a full recovery .

In her role as first lady , she championed the cause of literacy . She formed the Barbara Bush Foundation for Family Literacy in 1989 . That was the same year that she made public that she had been diagnosed in 1988 with Graves ' disease , an autoimmune disease that commonly affects the thyroid .

In 2010 , she was hospitalized for what doctors at the time described as a recurrence of Graves ' disease . She underwent heart surgery in 2009 after doctors found hardening in one part of her aorta . In 2008 , she was hospitalized after suffering abdominal pain . She underwent surgery for a perforated ulcer .

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She had been treated for pneumonia at a Houston hospital

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Bush is the wife of the 41st president , George H.W. Bush

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In her role as first lady , she championed the cause of literacy